Hemorrheological changes associated with brain death and their implications for potential organ donors

Successful transplantation of donor organs from brain-dead patients requires adequate maintenance of hemodynamic parameters. Blood flow and tissue perfusion are highly dependent upon hemorrheology. The aim of the present study was to evaluate hemorrheological parameters in potential organ donors compared to healthy volunteers. Whole blood-, plasma- and corrected blood viscosity, hematocrit, erythrocyte deformability, and erythrocyte aggregation were obtained in ten consecutive brain-dead patients and ten matched volunteers. Compared to controls, hematocrit and whole blood viscosity at high and medium shear rates and erythrocyte deformability were significantly decreased. Plasma viscosity was significantly increased in all patients. In the same group, a highly significant increase was observed at all shear rates when viscosity was corrected for hematocrit. Definite rheological abnormalities were found in the blood of brain-dead patients, something which might lead to impaired organ function after transplantation. Therefore, optimizing such parameters by special fluid management may be of importance in potential organ donors.